<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <title>Document</title>
  </head>
  <body>
    <script>
      // callee的作用是可以复制函数
      function fun() {
        console.log(arguments.callee);
      }
      fun();
    </script>
  </body>
</html>
